TRACON Pharmaceuticals inc. (NASDAQ:TCON) has highlighted updated clinical data from the pivotal trial of envafolimab in MSI-H/dMMR cancer patients that were recently presented by the company’s corporate partners, 3D Medicines and Alphamab Oncology.
In a presentation highlighting updated clinical results at the Chinese Society of Clinical Oncology (CSCO) 2020 Virtual Scientific Program entitled, 'Subcutaneous Injection of PD-L1 Antibody Envafolimab (KN035) in Advanced Tumors with Mismatch-Repair Deficiency,' single-agent envafolimab was shown to have a 32% confirmed objective response rate (ORR) by central radiographic review of 41 patients with MSI-H/dMMR colorectal cancer (CRC) who failed a fluoropyrimidine, oxaliplatin and irinotecan, and had at least two on-study tumor assessments.
Duration of response (DOR) was greater than or equal to 12 months in 75% of patients and overall survival (OS) was greater than or equal to 12 months in 65% of patients. The ORR in the overall population (N=103) was 43%, DOR was greater than or equal to 12 months in 92% of patients and OS was greater than or equal to 12 months in 75% of patients. Envafolimab demonstrated good tolerability and safety and there continued to be no infusion-related reactions.
Earlier data from this trial were presented by 3D Medicines and Alphamab Oncology at ASCO 2020, in a presentation entitled, 'Envafolimab (KN035) in Advanced Tumors with Mismatch-Repair Deficiency', at which time single-agent envafolimab was shown to have a 28% confirmed ORR by central radiographic review in 39 patients with MSI-H/dMMR CRC who failed a fluoropyrimidine, oxaliplatin and irinotecan, and had at least two on-study tumor assessments.
The trial enrolled 103 patients with MSI-H CRC, GC or with dMMR in other advanced solid tumors at clinical sites in China, in an open-label format with efficacy endpoints, including the primary endpoint of confirmed ORR determined by independent central review. MSI-H/dMMR status was assessed centrally for CRC and GC and locally for other tumors.
The confirmed ORR in MSI-H/dMMR colorectal cancer patients treated with envafolimab who failed a fluoropyrimidine, oxaliplatin and irinotecan reported at CSCO 2020 of 32% is similar to the 28% confirmed ORR reported in the Opdivo package insert in MSI-H/dMMR colorectal cancer patients who failed a fluoropyrimidine, oxaliplatin, and irinotecan, and the 27.9% confirmed ORR reported for Keytruda in MSI-H/dMMR CRC patients who failed a fluoropyrimidine, oxaliplatin and irinotecan seen in cohort A of the pivotal KEYNOTE-164 trial.
In a statement, James Freddo, TRACON chief medical officer said: “The CSCO 2020 data provide further clinical evidence that envafolimab’s activity is similar to that of Opdivo and Keytruda in MSI-H/dMMR cancer. Also impressive is the durability of response at 12 months."
He added: “Given the 4% ORR reported in the pivotal study of Votrient, the only approved therapy for refractory UPS and MFS, and the demonstrated efficacy of immune checkpoint inhibitors in these populations, we believe the clinical results of our ENVASARC pivotal trial, if positive, could position envafolimab as a transformative new standard of care for sarcoma patients.
"Moreover, the elimination of PD-L1 associated infusion-related reactions observed to date and the convenience provided by envafolimab as the only subcutaneously administered PD-L1 inhibitor currently being studied in registrational trials, could provide significant benefits for clinicians and their patients.”
TRACON is a clinical-stage biopharmaceutical company focused on the development and commercialization of novel targeted cancer therapeutics and utilizing a cost-efficient, CRO-independent product development platform to partner with ex-US companies to develop and commercialize innovative products in the US today.
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